db backend: mostly feature-complete

12 files changed, 496 insertions, 159 deletions

diff --git a/TagEditor.ui b/TagEditor.ui
new file mode 100644
index 0000000..a8a942b
--- /dev/null
+++ b/TagEditor.ui
@@ -0,0 +1,67 @@
+<?xml version="1.0" encoding="UTF-8"?>

+<ui version="4.0">

+ <class>Dialog</class>

+ <widget class="QDialog" name="Dialog">

+  <property name="geometry">

+   <rect>

+    <x>0</x>

+    <y>0</y>

+    <width>400</width>

+    <height>300</height>

+   </rect>

+  </property>

+  <property name="windowTitle">

+   <string>Dialog</string>

+  </property>

+  <layout class="QVBoxLayout" name="verticalLayout">

+   <item>

+    <widget class="QPlainTextEdit" name="textEdit"/>

+   </item>

+   <item>

+    <widget class="QDialogButtonBox" name="buttonBox">

+     <property name="orientation">

+      <enum>Qt::Horizontal</enum>

+     </property>

+     <property name="standardButtons">

+      <set>QDialogButtonBox::Cancel|QDialogButtonBox::Ok</set>

+     </property>

+    </widget>

+   </item>

+  </layout>

+ </widget>

+ <resources/>

+ <connections>

+  <connection>

+   <sender>buttonBox</sender>

+   <signal>accepted()</signal>

+   <receiver>Dialog</receiver>

+   <slot>accept()</slot>

+   <hints>

+    <hint type="sourcelabel">

+     <x>248</x>

+     <y>254</y>

+    </hint>

+    <hint type="destinationlabel">

+     <x>157</x>

+     <y>274</y>

+    </hint>

+   </hints>

+  </connection>

+  <connection>

+   <sender>buttonBox</sender>

+   <signal>rejected()</signal>

+   <receiver>Dialog</receiver>

+   <slot>reject()</slot>

+   <hints>

+    <hint type="sourcelabel">

+     <x>316</x>

+     <y>260</y>

+    </hint>

+    <hint type="destinationlabel">

+     <x>286</x>

+     <y>274</y>

+    </hint>

+   </hints>

+  </connection>

+ </connections>

+</ui>

diff --git a/numberator.cpp b/numberator.cpp
index 2497403..912c5e3 100644
--- a/numberator.cpp
+++ b/numberator.cpp
@@ -2,6 +2,8 @@
 #include "ui_numberator.h"

 #include "ui_TagListDock.h"

 

+#include <QMessageBox>

+

 Numberator::Numberator(QWidget *parent)

     : QMainWindow(parent)

     , ui(new Ui::Numberator)

@@ -14,6 +16,12 @@ Numberator::Numberator(QWidget *parent)
 {

     ui->setupUi(this);

 

+    connect(&proj, &SQLiteSaveFile::fileIOError, [=](auto e, QString errorName, QString description) {

+        Q_UNUSED(e);

+        qDebug() << errorName << ": " << description;

+        QMessageBox::critical(this, errorName, description);

+    });

+

     QDockWidget *dock = new QDockWidget(this);

     tagsDockUi->setupUi(dock);

     addDockWidget(Qt::LeftDockWidgetArea, dock);

@@ -45,26 +53,29 @@ Numberator::Numberator(QWidget *parent)
     connect(&saveOpenDialog, &QFileDialog::accepted, [=]() {

         settings.setValue("MainWindow/SaveAsFileDialogState", this->saveOpenDialog.saveState());

     });

-    connect(ui->actionSave_Project, &QAction::triggered, [=](bool checked){

-        Q_UNUSED(checked);

-        this->saveOpenDialog.setWindowTitle("Save Project as...");

-        disconnect(&this->saveOpenDialog, &QFileDialog::fileSelected, nullptr, nullptr);

-        connect(&this->saveOpenDialog, &QFileDialog::fileSelected,

-                &this->proj, &SQLiteSaveFile::saveAs);

-        this->saveOpenDialog.open();

+    connect(ui->actionSave_Project, &QAction::triggered, this, &Numberator::showSaveDialog);

+    connect(ui->actionOpen_Project, &QAction::triggered, [=](){

+        if (!showConfirmDiscardDialog())

+            return;

+

+        saveOpenDialog.setWindowTitle("Open Project...");

+        saveOpenDialog.setAcceptMode(QFileDialog::AcceptOpen);

+        if (saveOpenDialog.exec() == QDialog::Accepted)

+            proj.open(saveOpenDialog.selectedFiles().value(0));

     });

-    connect(ui->actionOpen_Project, &QAction::triggered, [=](bool checked){

-        Q_UNUSED(checked);

-        this->saveOpenDialog.setWindowTitle("Open Project...");

-        disconnect(&this->saveOpenDialog, &QFileDialog::fileSelected, nullptr, nullptr);

-        connect(&this->saveOpenDialog, &QFileDialog::fileSelected,

-                this, &Numberator::openFile);

-        this->saveOpenDialog.open();

+

+    connect(ui->actionNew_Project, &QAction::triggered, [=]() {

+        if (!showConfirmDiscardDialog())

+            return;

+

+        proj.clearNew();

     });

+    connect(ui->actionQuit, &QAction::triggered, [=]() {

+       if (!showConfirmDiscardDialog())

+           return;

 

-    connect(ui->actionNew_Project, &QAction::triggered,

-            &proj, &SQLiteSaveFile::clearNew);

-    connect(ui->actionQuit, &QAction::triggered, &QApplication::quit);

+       QApplication::quit();

+    });

     connect(ui->actionAbout, &QAction::triggered, &aboutDialog, &AboutDialog::open);

 

     connect(tagsDockUi->tagList->selectionModel(), &QItemSelectionModel::currentChanged,

@@ -79,8 +90,33 @@ Numberator::~Numberator()
     delete ui;

 }

 

-void Numberator::openFile(const QString &path)

+bool Numberator::showConfirmDiscardDialog()

 {

+    if (!proj.isMemory() || !proj.isDirty())

+        return true;

+

+    auto btn = QMessageBox::warning(this, "Discard unsaved changes?", "This document contains unsaved changes. Do you want to save these changes?",

+                         QMessageBox::Save | QMessageBox::Discard | QMessageBox::Cancel);

+

+    if (btn == QMessageBox::Cancel)

+        return false;

+

+    if (btn == QMessageBox::Save)

+        return showSaveDialog();

 

+    /* else, the discard button was clicked */

+    return true;

 }

 

+bool Numberator::showSaveDialog()

+{

+    saveOpenDialog.setWindowTitle("Save Project as...");

+    saveOpenDialog.setAcceptMode(QFileDialog::AcceptSave);

+    if (saveOpenDialog.exec() == QDialog::Accepted) {

+        QString fn = this->saveOpenDialog.selectedFiles().value(0);

+        qDebug() << QString("Calling saveas(%1)").arg(fn);

+        return proj.saveAs(fn);

+    }

+

+    return false;

+}

diff --git a/numberator.h b/numberator.h
index 21203cd..bf661db 100644
--- a/numberator.h
+++ b/numberator.h
@@ -24,8 +24,10 @@ public:
     Numberator(QWidget *parent = nullptr);

     ~Numberator();

 

-private slots:

-    void openFile(const QString &path);

+    bool showConfirmDiscardDialog();

+

+public slots:

+    bool showSaveDialog(); /* return true if saved successfully (i.e. no error, not cancelled), false otherwise */

 

 private:

     Ui::Numberator *ui;

diff --git a/numberator.pro b/numberator.pro
index 8783811..124dd61 100644
--- a/numberator.pro
+++ b/numberator.pro
@@ -6,7 +6,8 @@ CONFIG += c++2a
 
 
 win32:INCLUDEPATH += $$[QT_INSTALL_PREFIX]/../Src/qtbase/src/3rdparty/sqlite
-win32:SOURCES += $$[QT_INSTALL_PREFIX]/../Src/qtbase/src/3rdparty/sqlite/sqlite3.c
+win32:LIBS += -L$$[QT_INSTALL_PLUGINS]/sqldrivers -lqsqlite
+#win32:SOURCES += $$[QT_INSTALL_PREFIX]/../Src/qtbase/src/3rdparty/sqlite/sqlite3.c
 unix:LIBS += -lsqlite3
 
 # The following define makes your compiler emit warnings if you use
@@ -25,6 +26,7 @@ SOURCES += \
     main.cpp \
     numberator.cpp \
     sqlitebackend.cpp \
+    tagitem.cpp \
     taglistmodel.cpp \
     tagproptablemodel.cpp \
     tagview.cpp \
@@ -34,12 +36,14 @@ HEADERS += \
     aboutdialog.h \
     numberator.h \
     sqlitebackend.h \
+    tagitem.h \
     taglistmodel.h \
     tagproptablemodel.h \
     tagview.h \
     tagscene.h
 
 FORMS += \
+    TagEditor.ui \
     TagListDock.ui \
     aboutdialog.ui \
     numberator.ui
diff --git a/sqlitebackend.cpp b/sqlitebackend.cpp
index b95e18d..434f1e6 100644
--- a/sqlitebackend.cpp
+++ b/sqlitebackend.cpp
@@ -4,64 +4,102 @@
 

 #include "sqlitebackend.h"

 

-SQLiteSaveFile::SQLiteSaveFile(QObject *parent, QString filename) :

+SQLiteSaveFile::SQLiteSaveFile(QObject *parent) :

     QObject(parent)

-  , lastError(NoError)

-  , lastErrorString(QString())

-  , db(QSqlDatabase::addDatabase("QSQLITE", QUuid::createUuid().toString()))

-  , filename(filename)

-  , m_isOpen(false)

+  , m_lastError(NoError)

+  , m_lastErrorString(QString())

+  , m_open(false)

+  , m_dirty(false)

 {

-    connect();

+    clearNew();

 }

 

-bool SQLiteSaveFile::initDb(bool setCreationDate)

+bool SQLiteSaveFile::open(const QString &filename)

 {

-    for (auto const &q: {

-         "CREATE TABLE IF NOT EXISTS metadata (key TEXT, value TEXT)",

-         "CREATE TABLE IF NOT EXISTS tags (id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT, anchor_x REAL, anchor_y REAL, meta TEXT)",

-         "CREATE TABLE IF NOT EXISTS blobs (name TEXT, data BLOB)"}) {

-        if (!runSql(q))

+    qDebug() << "open";

+    {

+        QMutexLocker l(&m_dbMut);

+        QFile f(filename);

+        if (!f.exists()) {

+            setError(FileNotFoundError, QString("File \"%1\"does not exist.").arg(filename));

             return false;

-    }

+        }

 

-    if (setCreationDate) {

-        if (!setMetaLocked("creationTime", QDateTime::currentDateTimeUtc().toMSecsSinceEpoch()))

+        QSqlDatabase new_db(QSqlDatabase::addDatabase("QSQLITE", QUuid::createUuid().toString()));

+        new_db.setDatabaseName(f.fileName());

+        if (!new_db.open()) {

+            setDatabaseError(new_db);

+            new_db.close();

             return false;

+        }

+

+        m_db.close();

+        m_db = new_db;

+

+        /* Try to load image, ignore if image is unset */

+        QSqlQuery q("SELECT data FROM blobs WHERE name = 'image'", m_db);

+        if (!q.exec())

+            return setDatabaseError(q);

+        if (!q.next())

+            return setDatabaseError(q);

+

+        m_memory = false;

+        m_dirty = false;

+        m_open = true;

+        m_image = q.value(0).toByteArray();

     }

-

+    fileReload(); /* Call after unlocking mutex to allow accesses by receivers */

     return true;

 }

 

-bool SQLiteSaveFile::connect()

+bool SQLiteSaveFile::clearNew()

 {

-    QMutexLocker l(&dbMut);

-    resetError();

-    m_isOpen = false;

-    imageData = QByteArray();

+    qDebug() << "clearNew";

+    {

+        QMutexLocker l(&m_dbMut);

+

+        QSqlDatabase new_db(QSqlDatabase::addDatabase("QSQLITE", QUuid::createUuid().toString()));

+        new_db.setDatabaseName(":memory:");

+        if (!new_db.open()) {

+            setDatabaseError(new_db);

+            new_db.close();

+            return false;

+        }

 

-    bool newlyCreated = QFile(filename).exists();

+        QSqlDatabase old_db = m_db;

+        m_db = new_db;

 

-    db.setDatabaseName(filename);

-    if (!db.open()) {

-        setDatabaseError(db);

-        db.close();

-        return false;

-    }

+        if (!initDb(true)) {

+            m_db.close();

+            m_db = old_db;

+            return false;

+        }

 

-    if (!initDb(newlyCreated)) {

-        db.close();

-        return false;

+        old_db.close();

+        m_memory = true;

+        m_dirty = false;

+        m_open = true;

+        m_image = QByteArray();

     }

+    fileReload(); /* Call after unlocking mutex to allow accesses by receivers */

+    return true;

+}

 

-    m_isOpen = true;

+bool SQLiteSaveFile::initDb(bool setCreationDate)

+{

+    for (auto const &q: {

+         "CREATE TABLE IF NOT EXISTS metadata (key TEXT, value TEXT)",

+         "CREATE TABLE IF NOT EXISTS tags (id INTEGER PRIMARY KEY AUTOINCREMENT, name TEXT, anchor_x REAL, anchor_y REAL, meta TEXT)",

+         "CREATE TABLE IF NOT EXISTS blobs (name TEXT, data BLOB)"}) {

+        if (!runSql(q))

+            return false;

+    }

 

-    /* Try to load image, ignore if image is unset */

-    QSqlQuery q("SELECT data FROM blobs WHERE name = 'image'", db);

-    if (!q.next())

-        return setDatabaseError(q);

+    if (setCreationDate) {

+        if (!setMetaLocked("creationTime", QDateTime::currentDateTimeUtc().toMSecsSinceEpoch()))

+            return false;

+    }

 

-    imageData = q.value(0).toByteArray();

     return true;

 }

 

@@ -74,66 +112,50 @@ static sqlite3 *getSqliteHandle(QSqlDatabase &db) {
 

 bool SQLiteSaveFile::saveAs(const QString &filename)

 {

-    QMutexLocker l(&dbMut);

+    qDebug() << "saveAs" << filename;

+    QMutexLocker l(&m_dbMut);

     QFile f(filename);

-    QSqlDatabase old_db = db;

     QSqlDatabase new_db(QSqlDatabase::addDatabase("QSQLITE", QUuid::createUuid().toString()));

-    new_db.setDatabaseName(f.fileName());

-    if (!new_db.open()) {

-        setDatabaseError(new_db);

-        new_db.close();

-        return false;

+    {

+        new_db.setDatabaseName(f.fileName());

+        if (!new_db.open())

+            goto err_cleanup;

+

+        sqlite3 *old_handle = getSqliteHandle(m_db);

+        sqlite3 *new_handle = getSqliteHandle(new_db);

+        sqlite3_backup *bck = sqlite3_backup_init(new_handle, "main", old_handle, "main");

+        if (!bck)

+            goto err_cleanup;

+

+        if (sqlite3_backup_step(bck, -1) != SQLITE_DONE)

+            goto err_cleanup;

+

+        if (sqlite3_backup_finish(bck) != SQLITE_DONE)

+            goto err_cleanup;

+

+        m_db.close();

+        m_db = new_db;

+        m_memory = false;

+        return true;

     }

-

-    sqlite3 *old_handle = getSqliteHandle(db);

-    sqlite3 *new_handle = getSqliteHandle(new_db);

-    sqlite3_backup *bck = sqlite3_backup_init(new_handle, "main", old_handle, "main");

-    if (!bck)

-        goto err_cleanup;

-

-    if (sqlite3_backup_step(bck, -1) != SQLITE_DONE)

-        goto err_cleanup;

-

-    if (sqlite3_backup_finish(bck) != SQLITE_DONE)

-        goto err_cleanup;

-

-    db = new_db;

-    old_db.close();

-    return true;

-

 err_cleanup:

     setDatabaseError(new_db);

     new_db.close();

     return false;

 }

 

-bool SQLiteSaveFile::clearNew()

-{

-    QMutexLocker l(&dbMut);

-

-    QSqlDatabase new_db(QSqlDatabase::addDatabase("QSQLITE", QUuid::createUuid().toString()));

-    new_db.setDatabaseName(":memory:");

-    if (!new_db.open()) {

-        setDatabaseError(new_db);

-        new_db.close();

-        return false;

-    }

-

-    if (!initDb()) {

-        db.close();

-        return false;

-    }

-

-    imageData = QByteArray();

-    return true;

-}

-

 QList<Tag> SQLiteSaveFile::getAllTags()

 {

-    QMutexLocker l(&dbMut);

+    qDebug() << "getAllTags";

+    QMutexLocker l(&m_dbMut);

     resetError();

     QList<Tag> rv;

-    QSqlQuery q("SELECT (id, name, anchor_x, anchor_y, meta) FROM tags", db);

+

+    QSqlQuery q("SELECT id, name, anchor_x, anchor_y, meta FROM tags", m_db);

+    if (!q.exec()) {

+        setDatabaseError(q);

+        return QList<Tag>();

+    }

 

     while (q.next()) {

         rv << Tag {

@@ -153,39 +175,44 @@ QList<Tag> SQLiteSaveFile::getAllTags()
 

 bool SQLiteSaveFile::updateTag(Tag tag)

 {

-    QMutexLocker l(&dbMut);

+    QMutexLocker l(&m_dbMut);

     if (!runSql("UPDATE tags SET name=?, anchor_x=?, anchor_y=?, meta=? WHERE id=?", {

                tag.name, tag.anchor.x(), tag.anchor.y(), QJsonDocument::fromVariant(tag.metadata).toJson(), tag.id

            }))

         return false;

 

+    m_dirty = true;

     tagChange(TagChange::CHANGED, tag);

     return true;

 }

 

 bool SQLiteSaveFile::deleteTag(Tag tag)

 {

-    QMutexLocker l(&dbMut);

+    QMutexLocker l(&m_dbMut);

     if (!runSql("DELETE FROM tags WHERE id=?", {tag.id}))

         return false;

 

+    m_dirty = true;

     tagChange(TagChange::DELETED, tag);

     return true;

 }

 

 bool SQLiteSaveFile::createTag(Tag tag)

 {

-    QMutexLocker l(&dbMut);

+    qDebug() << "createTag";

+    QMutexLocker l(&m_dbMut);

     resetError();

-    QSqlQuery q("INSERT INTO tags(name, anchor_x, anchor_y, meta) VALUES (?, ?, ?, ?)", db);

+    QSqlQuery q("INSERT INTO tags(name, anchor_x, anchor_y, meta) VALUES (?, ?, ?, ?)", m_db);

     q.addBindValue(tag.name);

     q.addBindValue(tag.anchor.x());

     q.addBindValue(tag.anchor.y());

     q.addBindValue(QJsonDocument::fromVariant(tag.metadata).toJson());

+

     if (!q.exec())

         return setDatabaseError(q);

 

     Tag created_tag(q.lastInsertId().toLongLong(), tag);

+    m_dirty = true;

     tagChange(TagChange::CREATED, created_tag);

     return true;

 }

@@ -205,25 +232,34 @@ bool SQLiteSaveFile::setMetaLocked(std::initializer_list<QPair<QString, QVariant
 }

 

 bool SQLiteSaveFile::setMeta(const QString &key, const QVariant &value) {

-    QMutexLocker l(&dbMut);

+    QMutexLocker l(&m_dbMut);

+    m_dirty = true;

     return setMetaLocked(key, value);

 }

 

 bool SQLiteSaveFile::setMeta(std::initializer_list<QPair<QString, QVariant>> metas) {

-    QMutexLocker l(&dbMut);

+    QMutexLocker l(&m_dbMut);

+    m_dirty = true;

     return setMetaLocked(metas);

 }

 

-QVariant SQLiteSaveFile::getMeta(const QString &key) {

-    QMutexLocker l(&dbMut);

+const QVariant SQLiteSaveFile::getMeta(const QString &key) const {

+    QMutexLocker l(&m_dbMut);

     return getMetaLocked(key);

 }

 

-QVariant SQLiteSaveFile::getMetaLocked(const QString &key)

+const QVariant SQLiteSaveFile::getMetaLocked(const QString &key) const

 {

+    qDebug() << "getMeta " << key;

     resetError();

-    QSqlQuery q("SELECT value FROM metadata WHERE key=?", db);

+    QSqlQuery q("SELECT value FROM metadata WHERE key=?", m_db);

     q.addBindValue(key);

+

+    if (!q.exec()) {

+        setDatabaseError(q);

+        return QVariant();

+    }

+

     if (!q.next()) {

         setDatabaseError(q);

         return QVariant();

@@ -234,18 +270,22 @@ QVariant SQLiteSaveFile::getMetaLocked(const QString &key)
 

 bool SQLiteSaveFile::runSql(QString query, std::initializer_list<QVariant> bindings)

 {

+    qDebug() << "runSql " << query;

     resetError();

-    QSqlQuery q(query, db);

-    for (const QVariant &v : bindings)

+    QSqlQuery q(query, m_db);

+    for (const QVariant &v : bindings) {

         q.addBindValue(v);

+    }

 

-    q.exec();

-    return setDatabaseError(q);

+    if (!q.exec()) {

+        return setDatabaseError(q);

+    }

+    return true;

 }

 

 bool SQLiteSaveFile::loadImageFromDisk(const QString &filename)

 {

-    QMutexLocker l(&dbMut);

+    QMutexLocker l(&m_dbMut);

     QFile f(filename);

     resetError();

 

@@ -254,7 +294,7 @@ bool SQLiteSaveFile::loadImageFromDisk(const QString &filename)
         return false;

     }

 

-    imageData = f.readAll();

+    m_image = f.readAll();

     if (f.error() != QFileDevice::NoError) {

         setError(ImageReadError, QString("Failed to read image: %1").arg(f.errorString()));

         return false;

@@ -266,7 +306,8 @@ bool SQLiteSaveFile::loadImageFromDisk(const QString &filename)
                  {"imageLoadedTime", QDateTime::currentDateTimeUtc().toMSecsSinceEpoch()}}))

         return false;

 

-    return runSql("INSERT OR REPLACE INTO blobs(name, data) VALUES ('image', ?)", {imageData});

+    m_dirty = true;

+    return runSql("INSERT OR REPLACE INTO blobs(name, data) VALUES ('image', ?)", {m_image});

 }

 

 bool SQLiteSaveFile::reloadImageFromDisk()

@@ -287,11 +328,7 @@ Tag::Tag(long long id, QString name, qreal anchor_x, qreal anchor_y, QByteArray
     , name(name)

     , anchor(QPointF(anchor_x, anchor_y))

     , metadata(QJsonDocument::fromJson(metadata).object().toVariantMap())

-{

-}

-

-Tag::Tag()

-    : id(-1)

+    , valid(true)

 {

 }

 

@@ -300,23 +337,26 @@ Tag::Tag(long long id, const Tag &other)
     , name(other.name)

     , anchor(other.anchor)

     , metadata(other.metadata)

+    , valid(true)

 {

 }

 

-bool SQLiteSaveFile::setDatabaseError(const QSqlQuery &q)

+bool SQLiteSaveFile::setDatabaseError(const QSqlQuery &q) const

 {

     if (!q.lastError().isValid())

         return true;

 

-    setError(SQLiteError, QString("Project file database error: %1").arg(q.lastError().text()));

+    qDebug() << "Query error: " << q.lastError().text();

+    setError(SQLiteError, QString("Project file database error executing %1: %2").arg(q.executedQuery()).arg(q.lastError().text()));

     return false;

 }

 

-bool SQLiteSaveFile::setDatabaseError(const QSqlDatabase &db)

+bool SQLiteSaveFile::setDatabaseError(const QSqlDatabase &db) const

 {

     if (!db.lastError().isValid())

         return true;

 

+    qDebug() << "Database error: " << db.lastError().text();

     setError(SQLiteError, QString("Project file database error: %1").arg(db.lastError().text()));

     return false;

 }

diff --git a/sqlitebackend.h b/sqlitebackend.h
index 4dfd2f9..52faedc 100644
--- a/sqlitebackend.h
+++ b/sqlitebackend.h
@@ -16,86 +16,101 @@ enum TagChange {
 class Tag

 {

 public:

+    Tag() : valid(false) {}

     Tag(long long int id, QString name, qreal anchor_x, qreal anchor_y, QByteArray metadata);

-    Tag();

     Tag(long long int id, const Tag &other);

 

+    bool isValid() { return valid; }

+

     long long int id;

     QString name;

     QPointF anchor;

     QVariantMap metadata;

+

+private:

+    bool valid;

 };

 

 class SQLiteSaveFile : public QObject

 {

     Q_OBJECT

 public:

-    explicit SQLiteSaveFile(QObject *parent = nullptr, QString filename = ":memory:");

-    bool connect();

-    bool isOpen() { return m_isOpen; }

+    explicit SQLiteSaveFile(QObject *parent = nullptr);

 

     QList<Tag> getAllTags();

 

-    QByteArray getImage();

+    const QByteArray &getImage() const { return m_image; };

 

     bool updateTag(Tag tag);

     bool deleteTag(Tag tag);

     bool createTag(Tag tag);

 

+    bool isMemory() { return m_memory; } /* backend db points to temporary memory db */

+    bool isDirty() { return m_dirty; } /* backend db was changed since opening */

+    bool isOpen() { return m_open; } /* backend db is open */

+

     bool setMeta(const QString &key, const QVariant &value);

     bool setMeta(std::initializer_list<QPair<QString, QVariant>> metas);

-    QVariant getMeta(const QString &key);

+    const QVariant getMeta(const QString &key) const;

 

-    QString errorString() { return lastErrorString; }

+    const QString &errorString() const { return m_lastErrorString; }

     enum Error {

         NoError = 0,

+        FileNotFoundError,

         SQLiteError,

         ImageOpenError,

-        ImageReadError

+        ImageReadError,

+        MaxError

     };

-    inline const static QString errorNames[] =  {

+    inline const static QString errorNames[MaxError] =  {

                 [NoError] = "No Error",

+                [FileNotFoundError] = "File not found",

                 [SQLiteError] = "Database Error",

                 [ImageOpenError] = "Error Opening Image",

                 [ImageReadError] = "Error Reading Image"

             };

 

     Error error();

-    void resetError() { lastError = NoError; lastErrorString = QString(); }

+    void resetError() const { m_lastError = NoError; m_lastErrorString = QString(); }

 

 public slots:

     /** Save this project file under a new name. This changes the backend database this project file object points to, and copies all data.

      * Callers can continue to use the same project file object afterwards.

      */

     bool saveAs(const QString &filename);

+    bool open(const QString &filename);

     bool reloadImageFromDisk();

-    bool loadImageFromDisk(const QString &filename);

+    bool loadImageFromDisk(const QString &m_filename);

     bool clearNew();

 

 signals:

     void tagChange(TagChange change, const Tag &tag);

     void fileReload();

-    void fileIOError(Error e, QString errorName, QString description);

+    void fileIOError(Error e, QString errorName, QString description) const;

 

 private:

+    bool connect();

     bool initDb(bool setCreationDate=true);

     bool runSql(QString query, std::initializer_list<QVariant> bindings={});

 

     bool setMetaLocked(const QString &key, const QVariant &value);

     bool setMetaLocked(std::initializer_list<QPair<QString, QVariant>> metas);

-    QVariant getMetaLocked(const QString &key);

-

-    void setError(Error e, QString desc) { lastError = e; lastErrorString = desc; fileIOError(e, errorNames[e], desc); }

-    bool setDatabaseError(const QSqlQuery &q);

-    bool setDatabaseError(const QSqlDatabase &db);

-

-    Error lastError;

-    QString lastErrorString;

-    QSqlDatabase db;

-    QMutex dbMut;

-    QString filename;

-    QByteArray imageData;

-    bool m_isOpen;

+    const QVariant getMetaLocked(const QString &key) const;

+

+    void setError(Error e, QString desc) const { m_lastError = e; m_lastErrorString = desc; fileIOError(e, errorNames[e], desc); }

+    bool setDatabaseError(const QSqlQuery &q) const;

+    bool setDatabaseError(const QSqlDatabase &m_db) const;

+

+    mutable Error m_lastError;

+    mutable QString m_lastErrorString;

+    QSqlDatabase m_db;

+    mutable QMutex m_dbMut;

+    QString m_filename;

+    QByteArray m_image;

+

+    bool m_open;

+    bool m_dirty;

+    bool m_memory;

 };

 

 

diff --git a/tagitem.cpp b/tagitem.cpp
new file mode 100644
index 0000000..d251428
--- /dev/null
+++ b/tagitem.cpp
@@ -0,0 +1,31 @@
+#include "tagitem.h"

+

+TagItem::TagItem(const Tag &tag)

+    : valid(true)

+{

+    setFlags(QGraphicsItem::ItemIsMovable

+             | QGraphicsItem::ItemIsSelectable

+             | QGraphicsItem::ItemIsFocusable);

+    /* TODO text_it.setFlags(QGraphicsItem::ItemIgnoresTransformations);

+     */

+    tagUpdated(tag);

+}

+

+void TagItem::tagUpdated(const Tag &tag)

+{

+    m_tag = tag;

+    setText(tag.name);

+    setPos(tag.anchor);

+}

+

+QVariant TagItem::itemChange(QGraphicsItem::GraphicsItemChange change, const QVariant &value)

+{

+    if (change == ItemPositionChange) {

+        /* https://gist.github.com/csukuangfj/c2a06416062bec9ed99eddd705c21275#file-qgraphicsscenetest-cpp-L90

+         *

+         */

+        /* FIXME */

+

+    }

+    return QGraphicsItem::itemChange(change, value);

+}

diff --git a/tagitem.h b/tagitem.h
new file mode 100644
index 0000000..a248243
--- /dev/null
+++ b/tagitem.h
@@ -0,0 +1,32 @@
+#ifndef TAGITEM_H

+#define TAGITEM_H

+

+#include "sqlitebackend.h"

+

+#include <QGraphicsPixmapItem>

+

+

+class TagItem : public QGraphicsSimpleTextItem

+{

+public:

+    TagItem(const Tag &tag);

+    TagItem() : valid(false) {};

+

+    enum { TagItemType = UserType + 1 };

+    int type() const override { return TagItemType; }

+

+    bool isValid() { return valid; }

+

+    void tagUpdated(const Tag &tag);

+

+    Tag tag() { return m_tag; }

+

+protected:

+    QVariant itemChange(QGraphicsItem::GraphicsItemChange change, const QVariant &value) override;

+

+private:

+    Tag m_tag;

+    bool valid;

+};

+

+#endif // TAGITEM_H

diff --git a/tagscene.cpp b/tagscene.cpp
index 5b028a0..fb52574 100644
--- a/tagscene.cpp
+++ b/tagscene.cpp
@@ -1,6 +1,81 @@
 #include "tagscene.h"
 
-TagScene::TagScene()
+#include <QGraphicsSceneMouseEvent>
+
+TagScene::TagScene(SQLiteSaveFile &proj)
+    : proj(proj)
+{
+    reloadPicture();
+    reloadTags();
+
+    connect(&proj, &SQLiteSaveFile::tagChange, this, &TagScene::tagChanged);
+    connect(&proj, &SQLiteSaveFile::fileReload,
+            [=]() { reloadTags(); });
+}
+
+void TagScene::tagChanged(TagChange change, const Tag &tag)
+{
+    TagItem *it;
+
+    switch(change)
+    {
+    case TagChange::CREATED:
+        addTag(tag);
+        break;
+
+    case TagChange::DELETED:
+        it = tags.take(tag.id);
+        assert(it);
+        removeItem(it);
+        break;
+
+    case TagChange::CHANGED:
+        it = tags[tag.id];
+        assert(it);
+
+        it->tagUpdated(tag);
+        break;
+    }
+}
+
+void TagScene::reloadPicture()
+{
+    pix.loadFromData(proj.getImage());
+    if (pix_it)
+        removeItem(pix_it);
+    pix_it = new QGraphicsPixmapItem(pix);
+    addItem(pix_it);
+}
+
+void TagScene::addTag(const Tag tag) {
+    TagItem *it = new TagItem(tag);
+    addItem(it);
+    tags[tag.id] = it;
+}
+
+void TagScene::reloadTags()
 {
+    clear();
+    for (auto *it : tags.values()) {
+        delete it;
+    }
+
+    for (const Tag &tag : proj.getAllTags()) {
+        addTag(tag);
+    }
+}
+
+void TagScene::mouseDoubleClickEvent(QGraphicsSceneMouseEvent *event)
+{
+    QGraphicsItem *it = itemAt(event->scenePos(), QTransform());
+    if (!it) {
+        QGraphicsScene::mouseDoubleClickEvent(event);
+    }
+
+    TagItem *tagitem = qgraphicsitem_cast<TagItem *>(it);
+    if (!tagitem) {
+        QGraphicsScene::mouseDoubleClickEvent(event);
+    }
 
+    tagDoubleClicked(tagitem->tag());
 }
diff --git a/tagscene.h b/tagscene.h
index 823609e..006fffd 100644
--- a/tagscene.h
+++ b/tagscene.h
@@ -1,14 +1,42 @@
 #ifndef TAGSCENE_H
 #define TAGSCENE_H
 
+#include "sqlitebackend.h"
+#include "tagitem.h"
+
+#include <QGraphicsPixmapItem>
 #include <QGraphicsScene>
 
 
 
 class TagScene : public QGraphicsScene
 {
+    Q_OBJECT
+
 public:
-    TagScene();
+    TagScene(SQLiteSaveFile &proj);
+
+public slots:
+    void reloadPicture();
+    void reloadTags();
+
+signals:
+    void tagDoubleClicked(const Tag &tag);
+
+protected:
+    void mouseDoubleClickEvent(QGraphicsSceneMouseEvent *event) override;
+
+private slots:
+    void tagChanged(TagChange change, const Tag &tag);
+
+private:
+    void addTag(const Tag tag);
+
+    SQLiteSaveFile &proj;
+
+    QGraphicsPixmapItem *pix_it;
+    QPixmap pix;
+    QMap<long long int, TagItem*> tags;
 };
 
 #endif // TAGSCENE_H
diff --git a/tagview.cpp b/tagview.cpp
index abaefcb..b4e83dd 100644
--- a/tagview.cpp
+++ b/tagview.cpp
@@ -5,11 +5,13 @@
 #include <cmath>
 
 TagView::TagView(SQLiteSaveFile &proj)
-    : proj(proj)
+    : scene(proj)
+    , proj(proj)
     , saveCenterTimer()
 {
     setDragMode(QGraphicsView::ScrollHandDrag);
     setScene(&scene);
+    connect(&scene, &TagScene::tagDoubleClicked, this, &TagView::tagDoubleClicked);
 
     saveCenterTimer.setSingleShot(true);
     saveCenterTimer.setInterval(500);
diff --git a/tagview.h b/tagview.h
index eedd019..71b418c 100644
--- a/tagview.h
+++ b/tagview.h
@@ -10,6 +10,8 @@
 
 class TagView : public QGraphicsView
 {
+    Q_OBJECT
+
 public:
     TagView(SQLiteSaveFile &proj);
 
@@ -19,6 +21,9 @@ public slots:
     void zoomIn(qreal delta);
     void rotate(int angle);
 
+signals:
+    void tagDoubleClicked(const Tag &tag);
+
 protected:
     void wheelEvent(QWheelEvent *evt) override;